This invention is an improvement in applicant's prior U.S. Pat. No. 4,702,639 issued Oct. 27, 1987. In this patent, the disc-like anchoring element is rigidly connected to the lower end of the slalom post and projects radially from the normal cylindrical surface of the post. This radially projected position of this anchoring element is protected in its ineffective position by a wedge or radial extension of the post mounted on a sleeve around the post, which wedge prevents rotation of the sleeve with rotation of the post. Thus the twisting of the post moves the disc anchoring element from its ineffective position protected by the wedge to an effective position angularly spaced from its protected position and horizontally into the medium of snow, snow-ice, or ice surrounding the lower end of the slalom post. The wedge projection disclosed in this patent gives an irregular and thickened cross-sectional contour to the lower end of the slalom post, which not only complicates its construction, but also often is an undesirable feature.